Hot nights: US in July sets new record for overnight warmth

Talk about sizzling nights, America obtained some for the historical past books final month.

The continental United States in July set a record for overnight warmth, offering little aid from the day’s scorching warmth for individuals, animals, crops and the electrical grid, meteorologists stated.

The common low temperature for the Lower 48 states in July was 63.6 levels (17.6 Celsius), which beat the earlier record set in 2011 by just a few hundredths of a level. The mark just isn’t solely the most popular nightly common for July, however for any month in 128 years of record retaining, stated National Oceanic and Atmospheric Administration climatologist Karin Gleason. July’s nighttime low was greater than 3 levels (5.4 Celsius) hotter than the twentieth century common.

Scientists have lengthy talked about nighttime temperatures — mirrored in more and more hotter minimal readings that often happen after sundown and earlier than dawn — being essential to well being.

“When you have daytime temperatures that are at or near record high temperatures and you don’t have that recovery overnight with temperatures cooling off, it does place a lot of stress on plants, on animals and on humans,” Gleason stated Friday. “It’s a big deal.”

In Texas, the place the month-to-month daytime common excessive was over 100 levels (37.8 Celsius) for the primary time in July and {the electrical} grid was harassed, the typical nighttime temperature was a nonetheless toasty 74.3 levels (23.5 Celsius) — 4 levels (7.2 Celsius) above the twentieth century common.

In the previous 30 years, the nighttime low in the U.S. has warmed on common about 2.1 levels (3.8 Celsius), whereas daytime excessive temperatures have gone up 1.9 levels (3.4 Celsius) on the identical time. For many years local weather scientists have stated international warming from the burning of coal, oil and pure fuel would make the world heat sooner at night time and in the northern polar areas. A study earlier this week stated the Arctic is now warming 4 instances sooner than the remainder of the globe.

Nighttime warms sooner as a result of daytime warming helps make the air maintain extra moisture then that moisture helps entice the warmth in at night time, Gleason stated.

“So it is in theory expected and it’s also something we’re seeing happen in the data,” Gleason stated.

NOAA on Friday additionally launched its international temperature knowledge for July, displaying it was on common the sixth hottest month on record with a mean temperature of 61.97 levels (16.67 levels Celsius), which is 1.57 levels (0.87 levels Celsius) hotter than the twentieth century common. It was a month of warmth waves, together with the United Kingdom breaking its all-time warmth record.

“Global warming is continuing on pace,” Colorado meteorologist Bob Henson stated.


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